IET Wiring Regulations 18th Edition, On-Site Guide and Guidance Note 3 Bundle (A4:2026)

IET Wiring Regulations 18th Edition, On-Site Guide and Guidance Note 3 Bundle (A4:2026)

IET Wiring Regulations 18th Edition, On-Site Guide and Guidance Note 3 Bundle (A4:2026) brings together three of the most-used references for compliant electrical work, combining the core standard with practical installation and verification guidance. It’s ideal for anyone involved in design, installation, inspection, testing, certification and maintenance across domestic, commercial and industrial installations.

The bundle includes BS 7671:2018+A4:2026 (the consolidated 18th Edition Wiring Regulations, commonly known as the orange book), which incorporates all previous amendments and adds updated coverage for areas such as stationary secondary batteries, ICT functional earthing and equipotential bonding, Power over Ethernet (PoE) and Section 710 Medical Locations. Amendment 4 is published on 15 April 2026 and can be implemented immediately on publication.

For fast, on-the-job referencing, the On-Site Guide (BS 7671:2018+A4:2026), 9th Edition supports installations up to 100 A, three-phase, summarising key requirements in a convenient format and reflecting all four amendments. It includes updated topics such as bidirectional and unidirectional protective devices, stationary secondary batteries, revised rationale for maximum Zs values, guidance on RCD selection, and prospective fault current considerations.

To support verification and qualifications, Guidance Note 3: Inspection & Testing provides clear inspection and testing guidance for working electricians and those studying inspection and testing courses, updated to align with BS 7671:2018+A4:2026. It includes updates such as identification of conductors, prosumers’ electrical installations, recommended initial inspection frequencies, and maximum permissible measured earth fault loop impedance (EFLI).

Key Features

• Bundle includes BS 7671:2018+A4:2026, On-Site Guide (A4:2026) and Guidance Note 3: Inspection and Testing (A4:2026)
• BS 7671:2018+A4:2026 is the consolidated 18th Edition standard incorporating all previous amendments
• Updates include stationary secondary batteries, ICT functional earthing and bonding, Power over Ethernet and revised medical locations guidance
• Amendment 4 published 15 April 2026 and can be implemented immediately on publication
• On-Site Guide supports installations up to 100 A, three-phase in a quick-reference format
• On-Site Guide includes guidance on bidirectional and unidirectional devices, maximum Zs rationale, RCD selection and prospective fault current
• Guidance Note 3 supports safe inspection, testing and documentation, and helps learners preparing for inspection and testing qualifications
• Guidance Note 3 includes updates on conductor identification, prosumers’ installations, initial inspection frequencies and maximum permissible measured EFLI